Today's Gospel Lesson from Matthew 1: 
But as he considered these things, behold, an angel of the Lord appeared to him in a dream, saying, “Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is from the Holy Spirit."

Joseph was a righteous man we are told. That means he can be counted on to do the right thing. But what if knowing what the right thing is isn't clear. The Law says put her out. But Joseph is unwilling to subject her to public disGRACE. Get that, Joseph is already a man of grace. As Ratzinger said, "Joseph lives the Law as Gospel." He will dismiss her quietly.

But then the angel appears with a new revelation. And now Joseph faces another decision. Will he believe the revelation - that the impossible is possible? He will. He is a "son of Abraham", who believed the angel when the angel said he and his wife would conceive though they were in their 90s (try explaining that to Medicare). "Abraham believed," the Scripture says, "and it was reckoned unto him as righteousness."

Joseph believed and in doing so showed us what true righteousness is - not wooden adherence to an old law, but dynamic faith in Emmanuel, "God with us."